SOLANACEAE

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            1. SYSTEMATIC POSITION:
            Bentham & Hooker
            Division: Phanerogames (Seed Plants)
                 Class: Dicotyledones
                        Sub-class: Gamopetalae
                               Series: Bicarpellatae
                                      Order: Polemoniales
                                             Family: Solanaceae
           
            2. MORPHOLOGICAL CHARACTERS:
            Habit – Herbs or shrubs, mostly climbing vines.
            Leaves – Alternate, simple, exstipulate.
            Inflorescence – Usually an axillary cymes or sometimes axillary solitary.
            Flower – Bisexual, actinomorphic, hypogynous.
            Calyx – Sepals 5, united, persistent, valvate.
            Corolla – Petals 5, united, valvate.
            Androecium – Stamens 5 or sometimes 4 (didynamous), epipetalous.
            Gynoecium – Carpel 2, syncarpous, ovary superior, obliquely placed, bi-locular or imperfectly 4-locular by a false septum, ovules many in each locules, placentation axile.
            Fruit – A berry or capsule.

             


           4. COMPARATIVE SYSTEMATIC POSITION AND AFFINITIES:
            Bentham and Hooker have placed this family under the order Polemoniales. Hutchinson, Thorne, Cronquist put it under the order Solanales, while Takhthajan placed this family in the order Scorpulariales and Engler & Prantl in the order Tubiflorae.
            Solanaceae is allied to Convolvulaceae in both having pentamerous flowers, persistent calyx and bicarpillary ovary. However, Solanacese possess obliquely placed ovary and are predominantly erect, whereas these characters are absent in Convolvulaceae. In certain characters Solanaceae is closely allied to Scrophulariaceae, Boraginaceae and Polemoniaceae. The Solanaceae are considered to be the most closely allied to Scrophulariaceae from which they differ in the presence of bicollateral vascular bundles, usually actinomorphic corolla and four/five stamens.
                   5. ECONOMIC IMPORTANCE:
            Economically the family is fairly important. It comprises several plants of food value, medicinal, vegetables and ornamentals.
            1. Food yielding plants of the family are – Solanum tuberosum (Potato), S. melongena (Brinjal), Lycopersicon spp. (Tomato), Capsicum spp. (Chilli), etc.
            2. Drug yielding plants of the family are – Atropa belladonna, Withania somnifera, Datura stramonium, Hyoscyamus niger, etc.
            3. Ornamental plants of the family are – Petunia, Cestrum, Lycium, etc.
            4. Plants used for smoking and insecticide – Nicotiana tabacum, N. rustica, etc.

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